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We are now one of the new members of the Ford C-Max Hybrid dead battery club. There is no battery monitoring system (BMS) on our C-Max 2013 that works. Failure of the battery at highway speed could end your life as you lose steering and brakes, air bags. At 5 mph I had a hell of a time stopping the car! I REPEAT. FORGET ABOUT MPG'S FOR A MOMENT. IF YOUR 12 V BATTERY DIES YOUR CAR DIES PERIOD. IF THIS HAPPENS ON THE HIGHWAY THEN YOU MIGHT DIE LIKE ALL OF THE 31+GM OWNERS WHO HAD THE FAILED IGNITION SWITCH. PROTECT YOURSELF. Buy a volt meter from Amazon for under $3.00 that you can plug into the 12 Volt cigarette socket. A fully charged battery will read 12.8 Volts+ A charging system voltage will be at least 13.5 to 14.5 Volts. Use it regularly until Ford fixes the system. You will have piece of mind and a great way to monitor your car's battery. A dead battery will read 12 Volts that is what we had when the battery monitoring system kicked in 10 seconds before the car died, losing brakes, steering, flashers and everything else. Be prepared to use the emergency parking brake. Check your battery voltage daily until you get the meter. Buy a regular volt meter and check the system's voltage by using the two terminals located in the front right side of your vehicle. One is + and the post is - You NEVER know when the charging component will or has failed. That is one of the big silent problems. You just don't see it coming. Send a letter to Ford to first fix the BMS and second to add a visual voltage meter and Coolant Temperature gauge on the Left side of the panel (available in My View). They should also add parallel redundancy to the battery charging system with at least 3 systems and to redesign the system so that the car will not die once started if the battery dies. We live in Canada 50 miles from where this car was built but we are a 3rd world country to Ford. Write Ford USA. They can ignore me but not the USA citizens. Battery (12 v) failure MUST NEVER SHUT THE CAR DOWN WHEN BEING DRIVEN. NO POWER; NO POWER STEERING, NO POWER BRAKES, NO LIGHTS/FLASHERS AND MOST LIKELY NO AIR BAGS. If you do not see the battery being charged while operating the vehicle contact your Ford Dealer ASAP and perhaps don't drive the car. I am trying to warn all C-Max hybrid owners of this problem. We had the most recent upgrade done on October 23 2014 when our Navigation System was repaired, one day before the battery died. Ford tech's did not notice that the charging system was not working because no alarms were showing. The C-Max hybrid is different than a standard car. The ICE (engine) does not have a starting motor or an alternator. The EV motor starts the ICE. The Li ion high voltage battery charges the 12 V system. The 12 V system runs things like the radio, standard instrumentation and I believe the air bags. UPDATED 7 Nov 2014 Found dc/dc charger for battery was not working ......No Alarms Found high amp fuse with very heavy wire was replaced and solved the problem - it must have be shorting out putting a drain on the charging system and emptying the battery. Still not BMS update. You can access the charging system voltage and coolant temp via the ETM mode at startup. Suggest check regularly until you get a voltmeter and Ford fixes this end of the problem. It took 2 weeks but our C-Max is up and running - charging voltage is normally 14.3-4 Volts. Note: 13.4 V or so might indicate the fuse problem as was in our case once the Dc/Dc charger was replaced. Check the battery light is green located on top of the battery and very difficult to see.